Many DOD components and agencies are authorized to respond to save lives, protect property and the environment, and mitigate human suffering under imminently serious conditions, as well as to provide support under their separate established authorities, as appropriate. The provision of defense support is evaluated by its legality, lethality, risk, cost, appropriateness, and impact on readiness. When Federal military and civilian personnel and resources are authorized to support civil authorities, command of those forces will remain with the Secretary of Defense. DOD elements in the incident area of operations and National Guard forces under the command of a Governor will coordinate closely with response organizations at all levels (DHS, NRF, Jan 2008, 26)